Tiered Compilation, which was introduced in JDK 7, has been enabled by default and brings server VM startup speeds close to or on par with the client VM. For details on how to control the compiler, see the documentation for the java command.

Permament generation, where the VM stored internal native data structures, such as class information, has been replaced with metaspace. Metaspace eliminates java.lang.OutOfMemoryError: PermGen space errors. The java command introduces the option -XX:MetaspaceSize, which sets the maximum amount of native memory that can be allocated for class metadata. By default, the size is not limited. In addition, the experimental option -Xshare has been introduced, which reduces footprint and startup time by sharing loaded JDK classes between all Java processes on the same host.